Method of and apparatus for packaging bricks



Dec. 5, 1967 A. P. KONGER v METHOD OF AND APPARATUS FOR PACKAGING BRICKSFiled June 13, 1966 2 Sheets-Sheet l INVENTOR ALFRED P KO/VGER 1967 A.P. KONGER 4 3,356,013

I METHOD OF AND APPARATUS FOR PACKAGING BRICKS Filed June 13, 1966 2Sheets-Sheet 2 FIG. 3

INVENTOR ALFRED PKO/VGER E Q W United States Patent 3,356,013 METHOD OFAND APPARATUS FOR PACKAGING BRICKS Alfred P. Konger, McHenry, llll.,assignor to Signode Corporation, Qhicago, ill, a corporation of DelawareFiled June 13, 1966, Ser. No. 556,958 5 Claims. (Cl. 100-4) The presentinvention relates to a method of and an apparatus for packaging bricks,and has particular reference to the application of steel strapping toindividual stacks of bricks to provide tightly compacted unit packswhich are then assembled upon one another to produce a larger compositeunit or brick package consisting of a number of the individual unitbrick packs which are held together in their assembled relationship byelongated protective corner strips common to all of the packs and whichunderlie all of the straps and, in addition to their protectivefunction, serve to hold adjacent packs in contiguity.

In recent years a major step toward the efficient and economicalhandling of bricks has been the development of a brick packageconsisting of a number of individual pack units, each of which isencircled by a single peripheral loop of metal strapping, with thevarious pack units being maintained in longitudinal alignment andcontiguity by longitudinally extending corner strips at the four cornersof the package and about which the various metal straps are positioned.At one or two locations in the pack, openings for the forks of a lifttruck are provided by omitting a few longitudinally aligned bricks and,additionally, before the metal straps are applied, elongated paper,cardboard, wooden, or, more recently, elastomeric corner protectors arefolded around each of the four longitudinally extending corners of thepackage to provide L-shape corner strips which are confined in positionby the application of the metal straps from cutting into the adjacentcorners of the bricks and they also serve the purpose of tying thevarious unit packs together in substantial contiguity againstlongitudinal separation. It is to this general type of brick packagethat the present invention pertains.

Although brick packages of the general type briefly outlined above hasmaterially reduced the cost of brick handling, they have not provenaltogether satisfactory from the standpoint of package stability. It hasbeen found that frequently a brick package which, as it leaves thestrapping station, exhibits good compression and stability, is found tobe loose at the time it arrives in the field. Considering the individualunit packs of such a brick package, although the bricks which comprisesuch a unit pack may immediately after the strapping operation has beenperformed be tightly banded together, separation of the bricks tends tooccur under the slightest provocation, as for example under the jogglinginfluence of the boxcar, highway truck or other transportation medium.Furthermore, lateral separation forces come into existence each time thebrick package is lifted by a fork truck and the resultant brickseparation is cumulative so that after a given package has been thushandled a few times the brick separations will not close again when thepackage is released by the fork truck.

The causes for such latent brick package instability are well known bybrick manufacturers and the strapping machine industry alike. Principalamong them is the presence of loose kiln sand within the confines of thebrick package. This sand is a result of the kiln process and it adheresto bricks throughout the stacking operation so that intimate nesting ofadjacent bricks in the stack is prevented by the intervening sandparticles. Thus when a given stack is strapped to produce a unit brickpack, an

appreciable quantity of loose sand remains within the pack. In thestatic condition of the pack at the time it is initially encircled witha loop of strapping, the brick pack may have good compression and thestrap may exhibit the proper tension when tested with the fingers.However, as soon as handling of this brick pack takes place asheretofore described and repeated internal stresses are applied to thesame, the interface motion between adjacent bricks causes the sand tosettle out with the net result that the strap becomes progressivelyloose, even to the point where the pack will come apart during unloadingoperations utilizing a fork truck. Recognition of the adverse effects ofentrapped sand in brick packages is evidenced by prior attempts toeliminate such sand by the use of compressed air which is directedagainst the stacked bricks at the strapping station. Such a procedurehowever is not altogether satisfactory due to the dust problem whicharises and also due to the fact that intimate encounter of all bricksurfaces with the air jets is not attainable.

Another and equally important reason for latent package looseness isparticularly prevalent with textured antique brick where the unevensurfaces of the bricks prevent true rectangular nesting of adjacentbricks. Such antique type bricks invariably are provided with high spotsin the form of burrs or irregular pyramidal protuberances often rangingin height to as much as onequarter of an inch. These protuberances mayexhibit good compressional characteristics in an axial direction so thatthey will resist crumbling under full strap tension in the staticcondition of the brick pack, but as soon as the pack is subjected tohandling the lateral forces which are applied thereto as a result ofrelative brick displacements will shear, fracture or otherwise rupturethese protuberances or crumble them to powder form and, again, looseningof the strapped brick pack will result.

Since textured brick is subject to a combination of both loose sandentrapment and the abrasion or other collapse of surface irregularities,few brick packages are able to withstand the handling which isordinarily encountered in transporting them from the kiln to a givenscene of brick installation. Although many of the brick packages mayarrive intact at the scene of installation, internal brick damage Wherea loose package is concerned is not an infrequent continugency, somebricks being completely fractured and other possessing latent or hiddenfractures which are not readily visible and which therefore constitute ahazard in the erected brick structure.

A third reason for brick package looseness frequently exhibits itselfdirectly at the strapping station and a predicated upon the reluctanceof steel strapping to slide easily around the four corners of theindividual brick packs. After the loose loop of strapping has beeninitially shrunk upon a pack and actual tensioning takes place, thetensioning Wheel or roller which is employed for tensioning purposes isobliged to overcome successively the frictional resistance which isoffered to the strapping at each of the four corners involved but,frequently, the maximum tension of which the tensioning wheel is capableis largely dissipated in the first three proximate corners so that theremote corner does not receive adequate tension to draw the strappingtightly around all four sides of the pack. This phenomenon of strappingprocedure, when coupled with occluded sand and brick surfaceirregularities presents brick packaging problems which have long plaguedthe industry.

The present invention is designed to overcome the abovenoted limitationsthat are attendant upon the packaging of bricks and, toward this end theinvention contemplates the provision of a novel method of brickpackaging wherein stacks of bricks are strapped to produce individualbrick packs and wherein the thus strapped brick packs are positioncd inend-to-end relationship and maintained in such relationship bylongitudinal corner strips as heretofore described in connection withconventional brick packaging, but in which the stacks which, whenstrapped, make up the individual brick packs, are subjected to highfrequency vibration immediately prior to and during the strappingoperation, thus resulting in a completed brick package which will retainits stability indefinitely throughout all of the contingencies which areencountered during the commercial handling of the package from the timeit leaves the strapping station at the kiln to the time it is deliveredin the field.

It is well known that various articles, particularly granular materialsand also certain bulk articles may be compacted to smaller proportionsby subjecting them to high frequency vibration so that they will settleby gravity and assume a more intimate or condensed relationship forpackaging purposes. Thus, containers are sometimes vibrated to agitatethe contents thereof while filling, to the end that a greater mass, byweight, may fill a given container. However, where vibratory effects areapplied to prepositioned rectangular articles which themselves areincompressible, no appreciable reduction in volume takes place. In fact,vibration alone offers no advantage even when subsequent packaging,either in containers or by strapping or tying, is resorted to. However,in the case of textured brick, high frequency vibration coupled withlateral stack compression and simultaneous strapping so as to impartadditional compressional forces to the brick stack in centripetalfashion in all inward directions, offers numerous advantages for anunexpected nature.

In the first place, according to the present invention, vibration takesplace while the stack of bricks is in the open so to speak so that theloose sand is shaken from the stack and is thus isolated, none of thisreleased sand being packaged. Vibration takes place while the stackclosely approaches the strapping station so that much of the sand isshed from the stack before it undergoes strapping and vibration iscontinued during the strapping operation where centripetal forces areapplied to the stack to compact it in all directions so that not onlydoes a final sand evacuation take place but any sand particles whichfail to become dislodged at this time will seek a common level or findtheir way into the porous surface regions of the bricks where they willassume innocuous out-of-the-way positions and not impede brickcontiguity. This settling of the hard-to-dislodge particles takes placein four directions with respect to each brick, i.e. vertically in bothdirections, and transversely in both directions with respect to themajor axes of the brick pack.

Secondly, the high frequency vibration which is applied to the stack ofbricks during the actual strapping operation results in a forcedabrasion of adjacent brick surfaces, each upon the other, so that thevarious pyramidal or other protuberances on the surfaces of the bricksare literally worn away progressively as the tension in the appliedstrapping increases. During such abrasion, the particles or products ofabrasion which are created due to disintegration of the protuberancesare carried away from the stack under the vibratory influences which areprevalent so that they offer no obstacle to the attainment of ultimatebrick contiguity. Whereas a protuberance which, in the absence ofvibration might withstand full strapping tension, in the presence ofsuch vibration will be subjected to lateral forces tending to shear,rupture and ultimately grind such protuberance to nothingness and carryaway the products of abrasion.

Finally, the effects of vibration upon the stack during the strappingoperation allows the strapping to flow so to speak around the fourcorners of the brick packs with comparative ease. Thus, the tensioningWheel or other tensioning instrumentality employed for strap tensioningpurposes, will exert a far reaching and equalized tensioning influencewhich extends completely around the pack so that equal tension willultimately result in each of the four linear spans of the strapping loopat all four sides of the pack. Still further, according to the presentinvention, the vibratory effects which are applied to the stack are notuniform with respect to each brick in the stack. Positive vibration isapplied only to the bricks in the lowermost tier of bricks in the stack.Thus, the bricks are not vibrated in unison, nor is the container i.e.the strapping which ultimately binds the package, vibrated so that itdoes not impart its vibratory motions to the bricks. The bricks areprepositioned in approximate face-to-face relationship and the amplitudeof vibratory motion involved is not so great as to disturb relativebrick orientation. There is no tumbling of articles and each brick whichoriginally is bounded on four sides by four other bricks, retains itspositional relationship with respect to such four bricks throughout theentire vibration cycle so that when vibration has ceased and thestrapping operation is complete, such a brick remains confronted by thesame four adjacent bricks as opposed it during the initial stackingoperation. Because adjacent bricks retain their opposed positionalrelationship during the entire vibratory cycle, the aforementionedabrasive action between adjacent opposed brick surfaces will take place.Each pair of opposed brick surfaces will, due to pogressivecompressional forces tending to bring them together under the influenceof progressive tensioning in the strapping exert a rapid and repeatedabrasive action each upon the other. Thus, any high spot or protuberanceexisting on either surface will rapidly be worn away whereas, withindiscriminate tumbling of loose articles, there is no assurance thatsuch a high spot or protuberance would encounter sufiicient abrasion toeradicate it.

The provision of a method of packaging bricks such as has briefly beenoutlined above constitutes the principal object of the presentinvention.

Another and important object of the invention resides in the provisionof a commercially practical apparatus by means of which the aboveoutlined method may conveniently be carried out. This object isaccomplished by the maintenance of an assembly line type of conveyorsystem wherein the bricks are assembled at a stacking station andconducted in successive stacks to a strapping station. The individualstacks consist of vertically arranged tiers of bricks supported on theirstretcher sides and each stack is of one brick width with the variousbricks in each tier being disposed in side face to side face contiguity.As the various succesive stacks approach the strapping station, a pairof opposed compression plates at a pre-cornpression station engage theopposite sides of the stacks for truing purposes and also for theapplication of relatively light compression to the stacks. The conveyorsystem is of the intermittent type and each indexing operation thereofserves to bring the leading stack on the conveyor into accurate registerwith a strapping chute and at the strapping station and to convey apreviously strapped stack from such station. At a region which is commonto the exit end of the pre-compression station and to the entrance endof the strapping station, a vibrator plate of full conveyor width iscaused to underlie the trailing edge regions of all of the bricks in thelowermost tier of bricks at the strapping station, as well as theleading edge regions of all of the bricks in the lowermost tier ofbricks awaiting entry into the strapping station. Thus, uponenergization of the vibrator plate, vi bratory effects are imparted toboth adjacent stacks, i.e. the stack undergoing strapping at thestrapping station and the next adjacent stack awaiting entry into thestrapping station and, at such time, undergoing pre-compression.

An additional feature of the present apparatus resides in the provisionof auxiliary compression means directly at the strapping station toindividually apply relatively high inward compression to the stack fromthe opposite sides thereof during the time that the loose loop ofstrapping is being shrunk upon the stack, and to augment the spasmscentripetal compression which is offered to the stack during actualstrap tensioning. This latter means is in the form of a pair ofcompression jaws which are of full stack height and which engage theopposite sides of the stack for individual stack truing and compressionpurposes, particularly in the medial vertical regions of the stack wherethe strapping has less tendency to exert inward force upon the stackthan it does in the corner regions.

It is to be distinctly understood that the apparatus illustrated hereinrepresents merely one practical embodiment which has been developed forthe commercial application of the present brick packaging method andthat other apparatus capable of performing the essential method steps ofthe invention are contemplated and may be developed in the future.Therefore, irrespective of the particular apparatus employed, theessential features of the invention remain substantially the same.

Numerous other objects and advantages of the invention, not at this timeenumerated, will become readily apparent as the nature of the inventionis better understood.

In the accompanying two sheets of drawings forming a part of thisspecification, one illustrative embodiment of the present brickpackaging method, together with the best known means for carrying outthis method have been disclosed.

In these drawings:

FIG. 1 is a fragmentary perspective view, partly in section, of aportion of an exemplary form of brick packaging apparatus by means ofwhich the present method may be effectively carried out, the view beingtaken in the immediate vicinity of the strapping station;

FIG. 2 is an enlarged fragmentary side elevational view of a portion ofthe structure shown in FIG. 1 and illustrating specifically astack-vibrating unit employed in connection with the invention;

FIG. 3 is an end perspective view of the apparatus taken from thedischarge end thereof;

FIG. 4 is a perspective view of a fragmentary portion of the apparatusframework in the vicinity of the vibrating station and showing thevibrator assembly operatively applied thereto;

FIG. 5 is a sectional view taken on the vertical plane represented bythe line 55 of FIG. 4and in the direction of the arrows; and

FIG. 6 is a perspective view of a strapped brick pack unit showing thesame severed from a larger brick package which has been packagedaccording to the present invention.

Referring now to the drawings in detail, a typical brick package whichhas been assembled from individual bricks and strapped according to themethod of the present invention appears in FIG. 1 and has beendesignated in its entirety at it The package is comprised of a pluralityof individual self-sustaining unit packs 12, one of which is shown inFIG. 6. The package 1% does not deviate appreciably in outwardappearance from a conventional brick package and, in the exemplary formwhich has been selected for illustration herein, the arrangement isgenerally cubic and consists of four of the unit packs 12 arranged incontiguous face-to-face longitudinal alignment. Each unit pack is handedby a metal steel strap 14 and the various unit packs are held togetheragainst longitudinal separation by longitudinally extending cornerprotectors or strips 16 which are L-shape in transverse cross sectionand underlie the various straps 14 as is customary in connection withsimilar brick packages. At selected regions of the package It)longitudinal rows of bricks are omitted in stacking the bricks, thusdefining openings 18 which preferably extend completely through thepackage and which are designed to receive the tines of a fork lift truckby means of which the package as a whole may be transported.

The specific dimensions of the individual bricks and their stackeddisposition may be varied but for exemplary purposes herein each unitpack 12 may be considered to be comprised of textured standard Americanbricks 20 supported on their stretcher sides with the correspondingbricks of adjacent packs being disposed in end-to-end contiguity.

As previously stated, the brick package 10 described above does notdiffer in outward appearance from a conventional brick package and itdiffers structurally therefrom only in that it possesses greaterstability under conditions of handling and greater stability underconditions of handling and transportation, this stability being impartedto it, as will be described presently, by reason of its method ofassembly according to the present invention.

Referring now to FIGS. 1 and 3, the preliminary procedure involved inproducing the package 10 wherein unit stacks 22 of bricks are erected ata loading station (not shown) and conducted on a live conveyor assembly24 to a strapping station S for production of the unit packs 12 isincidental to the present method and no claim is made herein to anynovelty associated with this procedure per se. Such a procedure has beenillustrated and described in detail in the aforementioned copendingapplication, Ser. No. 497,050 now Patent No. 3,329,262 which issued July4, 1967 and reference may be had thereto for a full understandingthereof. it is deemed sufficient for purposes of disclosure herein tostate that the individual brick stacks 22 are erected at the strappingstation in end-to-end contiguity as shown in FIG. 1 and that the liveroll conveyor 24 is indexed in step-by-step fashion to advance thestacks forwardly in succession to the strapping station S where they areindividually strapped by a conventional strapping machine 36 which maybe a Signode or other machine. During such intermittent advancing of thestacks 22, the angular material which forms the corner strips 16 isprogressively applied under tension to the four longitudinal corners ofthe continuously stacked bricks as they are advanced toward thestrapping station. At this latter station a loop of steel strapping 32is caused to encircle each unit stack 22 by means of a conventionalstrapping chute 34 from which the strapping is forcibly pulled by meansof the strapping machine 30 to shrink the loop 32 upon the stack.Thereafter the strapping machine 30 tensions the loop and applies a seal35 (FIGS. 1 and 6) to the overlapping end portions of the loop afterwhich the free end portion of the strapping is severed to free the thuscreated unit pack 12 from the source of strapping, all in the manner ofconventional strapping machine operation. The severed strap, in thusbinding the bricks 20 of the unit pack 12 together, also captures thevarious lengths of corner strip material 16 which have been applied tothe stack. The thus banded unit packs 12, securely bound to one anotherby reason of the tension in the corner strip material 16, areperiodically advanced on the conveyor 24 and, at a suitable severingstation (not shown) they may be separated into individual brick packages10 of four unit packs each or of any other desired brick pack multiple.

Still referring to FIGS. 1 to 3 inclusive, according to the presentinvention, means are provided for imparting vibratory effects to eachbrick stack 22 while it is undergoing strapping at the strappingstation, and also for imparting such vibratory effects to the nextadjacent stack which immediately precedes the strapping station.Accordingly, the conveyor 24 has associated therewith a pneumaticvibrator unit or assembly 46 (see also FIG. 4) which is secured to theconveyor plate proper 42 and which, during each strapping operation,serves to support thereon the trailing edge regions of all of the bricks26 in the lowermost tier of bricks of the unit stack 20 undergoingstrapping, and also the leading edge regions of all of the bricks in thelowermost tier of bricks of the next succeeding unit stack awaitingentry into the strapping station during the next apparatus cycle.

Specifically, the conveyor 24 involves in its general organization astationary framework 44 including opposed side rails 46 between whichthere extends the usual series of live rolls 48. The rolls 48 are powerdriven in unison, suitable control means, which forms no part of thepresent invention and which therefore has not been disclosed, beingprovided for periodically indexing the rolls to advance the stackedbricks supported thereon toward the strapping station S in increments ofmotion equal to the longitudinal extent of one unit stack.

The live rolls 4-8 are interrupted at the strapping station S and haveinterposed therebetween at substantially the horizontal level of therolls the aforementioned vibrator unit or assembly 40. This vibratorunit is shown in detail in FIGS. 2 and 4. The aforementioned vibratorplate 42 is in the form of an elongated bar having a smooth planar uppersurface provided with a bevelled edge 50 to facilitate sliding movementof the various bricks onto the plate. The plate extends completelyacross the effective reach of the conveyor 24 and the end regionsthereof are yieldingly supported on portions of the conveyor framework44 by means of respective flexible mounts (FIG. each including upper andlower tubular compression members 51 and 52 of rubber or other suitableresilient elastomeric material which straddle a mounting plate 53secured by bolts 54 to a portion of the framework 44, the plate 53 beingprovided with a clearance opening 55 therethrough for reception of afloating centering stud 56 which depends from the underneath side of theplate 42 and passes through both compression members 51 and 52. A nutand washer assembly 58 retains the various parts of the flexible mountin position.

A pneumatic vibrator motor 60 is bolted as at 62 to the underneath sideof the vibrator plate 42 at an appropriate medial region of the latterand is adapted to be supplied with compressed air through a flexibleconduit 64 leading from a suitable source (not shown) of such air. Thevibrator motor 60 may be of any conventional construction, there beingnumerous commercially available motors capable of imparting thenecessary vibratory eifects to the plate 42 and the bricks 20 supportedthereon, one such motor which has been found satisfactory for thepurposes intended being manufactured and sold by Vibro-Plus Products,Inc. of Stanhope, NJ. and designated as Model EP 40. Irrespectivehowever of the particular vibratory mechanism employed the essentialfeatures of the invention remain substantially the same. Vibratorymotors of the general type disclosed herein consist essentially of amotor housing within which there is disposed an eccentric or unbalancedrotor of appreciable mass and which, when rotated at relatively highspeeds, imparts vibratory motion to the housing within which it isrotatably journalled. The particular disposition of the motor 60 on theunderneath side of the vibrator plate 42 is not critical and, althoughthe motor is shown in FIG. 4 as being substantially centered between theends of the plate, it is within the purview of the present invention tosecure the motor at other locations along the plate.

Referring again to FIGS. 1 and 3, a region which spans several unitstack lengths along the conveyor 24 constitutes a pre-compressionstation and has been designated by the bracket PCS. At this stationmeans are provided for centering the various unit stacks 22 on theconveyor reach and also for imparting to the bricks contained therein apredetermined degree of compression in the transverse direction of theconveyor. Accordingly, a fixed pressure plate or compression jaw 70extends vertically upwardly from the upper side of the conveyor reachand is opposed by a movable compression plate or jaw '72. The movablejaw 72 is carried on the distal ends of a plurality of plungers 74 whichproject from respective pneumatic cylinders 76 supported on brackets 78which in turn are carried by vertical standards 80 which projectupwardly from the framework 44 of the conveyor 24. Flexible conduits 82connect the various cylinders 76 to a source of compressed O 0 air andsuitable control valve means (not shown) is provided for supplying airselectively to the opposite ends of the cylinders 76 to control theoperation of the movable pressure plate or jaw 72.

Means are provided directly at the strapping station S for similarlyimparting to the individual brick stacks 22 a relatively great degree ofinward compression in the transverse direction of the conveyor 24, suchcompression taking place during the actual strapping operation.Accordingly, a pair of slightly spaced apart compression rollers 1 0extend upwardly from the conveyor reach and have their lower endsrotatably journalled in a bracket 102 secured to one of the side framemembers 46 of the conveyor framework. The upper ends of the compressionrollers 100 are rotatably journalled in portions of a conveyorsuperstructure 104. On the opposite side of the conveyor 24, the rollers100 are opposed by a pair of vertically disposed movable compressionbars 106, each bar being carried by a bracket 108 supported on the outerend of a plunger 110 which projects from a cylinder 112 mounted on abracket 114 secured to one of the standards 80. Flexible conduits 116are provided for conducting compressed air to the opposite ends of thecylinders 112. The plungers and cylinders 110, 112 and the mountings andcontrols for the latter are similar to these described in connectionwith the movable pressure plate 72. In order to protect the sides of thebricks 20 from undue abrasion, the two compression bars 106 are eachprovided with a suitable elastomeric or other resilient brickengagingcontact strip 107.

A description of the operation of the abovedescribed brick packagingapparatus 10 will sutfice largely for a description of the methodinvolved in the present invention, although it is to be distinctlyunderstood that the practicing of the method is not dependent upon anyparticular apparatus. In its broadest aspect the method of the presentinvention may be carried out by any apparatus having associatedtherewith mechanism for effecting vibration of successive brick stacksat a strapping station, a means for compressing the stack in atransverse direction, and strapping facilities for binding the stackduring vibration of the latter so that the plane of the strapping loopextends in a transverse direction.

Assuming that the necessary control facilities are provided foreffecting the required machine operations such as the periodic indexingof the conveyor 24; the inward projection of the movable pressure plate72 toward the fixed pressure plate 70 to apply pre-compression to thenext several brick stacks 22 approaching the strapping station; thesimilar inward projection of the two compression bars 106 to compact thebrick stack at the strapping station during vibration and strappingthereof; energization of the vibratory motor 60 to agitate the stack;and actuation of the strapping machine 30; the unit stacks 22 areinitially set up or erected at the loading station and, from thence theyare periodically advanced in step-bystep fashion toward the strappingstation S. During this intermittent advancement of the unit stacks, thecorner strip material 16 is applied under tension in the manner setforth in the aforementioned application of Martin et al., Ser. No.497,050.

The indexing of the conveyor 44 is so controlled that as the leadingunit stack 22 of bricks approaches the strapping station S, the lowerleading transverse edge of such stack will come to rest as shown in FIG.2 in an approximately centered position on the vibrator plate 42. Thepreceding unit stack will, at this time, have been pushed forwardly onthe conveyor to a position wherein its lower trailing edge will rest onthe plate 42 with the two stacks 22 existing in substantial contiguity.At this time energization of the vibrator motor 60 will take place whileat the same time the cylinders 76 will be actuated so as to project theplungers 74 therefrom and cause inward movement of the movable pressureplate 72 toward the fixed pressure plate 70, thus aligning the stacks 22which are disposed between these pressure plates with the strappingstation and also applying a moderate degree of inward transversepressure to the bricks of such stacks. At the same time, the strappingmachine 30 will be set into operation.

It is to be observed at this point that the vibratory effects of thevibrator plate 42 will be imparted to both unit stacks 22 which arepartially supported on the vibrator plate 42 and these vibratory effectswill be distributed to all of the bricks in the two stacks. Due to theresilient mounts at the opposite ends of the vibrator plate 42,vibration is confined largely to the vibrator assembly 49 itself and tothe two unit stacks 22 supported thereon with only a modicum ofvibration being transmitted to adjacent brick stacks or to the frameworkin the immediate vicinity of the strapping station. In this manner thenoise level is maintained within reasonable limits.

During such vibration of the two stacks in the vicinity of the strappingstation S, the prepositioned bricks 20 in the stacks do not noticeablychange their positional relationship with respect to one anotheralthough a minute rubbing action between the various opposed bricksurfaces takes place. In the leading stack at the pre-compressionstation PCS, the bricks are compressed together in the transversedirection of the stack so that the major surfaces of the bricks are thussubjected to such rubbing or abrasive action. Vibration of the brickstherefore serves a two-fold purpose. Firstly it serves to agitate thebricks and thus shake loose any adhering particles of sand which havebeen carried over from the kiln. Where high textured or antique brick isconcerned, the irregular surface configuration thereof is such that theadjacent opposed surfaces of the fresh bricks in the stack will notinitially be in completely intimate face-to-face contact so that theloosened sand particles may readily find their way by gravity downwardlythrough the stack crevices for discharge therefrom. Secondly, due to therelatively light degree of inward or transverse compression imparted tothe stack as a whole by the two pressure plates 7 and 72, a certainamount of abrasion or self-sanding of the opposed major faces of thebricks will occur, thus wearing down any high spots or protuberances, ofwhich there are many on antique type brick. The abrasion of such protuberances creates additional sand which also is carried downwardlythrough the stack crevices by gravity to a point. of discharge. Asvibration continues and the two pressure plates continue to exert theircompressional forces on the stack, the various bricks move slowly intomore intimate contact, all the while shedding kiln sand and the productsof abrasion. As soon as the strapping operation which is being performedupon the next preceding stack directly at the strapping station S hasbeen completed to produce one of the finished strapped unit packs 12,stack compression is relieved momentarily and an indexing operation ofthe conveyor 24 serves to advance such unit pack from the strappingstation and transfer the next succeeding unit stack (now partiallydepleted of sand and somewhat intimately compressed) to the strappingstation where it shares its supported position on the vibrator plate 42with a succeeding unit stack which has been advanced to the leadingposition in the pre-compression station PCS.

The new and thus partially treated stack at the strapping stationbecomes subjected to simultaneous vibration, compression and strappingas soon as the vibration motor 60 and strapping machine 30 are energizedin the normal progression of the apparatus cycle. At the time theseinstrumentalities are energized, the movable pressure bars 106 arecaused to move toward the fixed pressure rollers 100 to engage the stackbetween the bars and rollers and thus apply a relatively great degree ofcompression in a transverse direction to the stack. The net effect ofthis combined vibration and transverse compression is similar to theeffect previously produced at the pre-compression station only it issomewhat intensified. At the pre-compression station most of the largerparticles of sand are removed from the stack, leaving only the fines tobe removed. Furthermore, the adjacent bricks now being in more intimaterelationship than they were at the time of the arrival of the stack atthe pre-compression station, and being under greater compression, aremore thoroughly scrubbed by the resulting abrasive action. Finally,since the surfaces of antique type brick is highly porous, such fines asdo not have time to settle through the stack to a region of dischargewill become entrapped between adjacent opposed brick surfaces but theywill not appreciably impede brick surface-to-surface intimacy orcontiguity because these fines readily find nesting places within thenumerous surface pores of the bricks so that in the ultimate analysis ofthe combined vibrational and compressional phenomena involved, adjacentbricks are to all intents and purposes in complete contiguity and nofurther reduction in over-all stack volume can take place regardless ofthe degree of compression imparted thereto.

In addition to the transverse compression which is offered to thevibrating stack at the strapping station S by the pressure bars 196 androllers 100, further and centripetal compression is offered the stack asa result of the strapping operation. As soon as slack has been taken upin the encircling loop 32 of strapping and the tensioning operation isinitiated, this additional compression is imparted to the stack, thusintensifying the abrasive action which takes place between the majorfaces of the bricks, and also exerting vertical compression on the stackto augment the static vertical compression normally prevalent by reasonof the weight of the individual bricks, one upon another. In thismanner, not only are the vertical opposed major faces of the brickssubjected to an abrasive sand removal operation, but so also are thehorizontal minor surfaces of the bricks.

The apparatus is cyclic in its operation and a single apparatus cyclemay be regarded as embodyin such operations as take place in-betweensuccessive conveyor indexing operations during which time a fresh unitstack 22 arriving at the pre-compression station PCS is preliminarilytreated as heretofore described, and a preliminarily treated unit stackarriving at the strapping station is further treated and strapped. Theapparatus is readily susceptible to semiautomatic operation underpush-button control, or to fully automatic operation.

The invention is not to be limited to the precise method steps describedherein, nor to the exact structural arrangements shown in theaccompanying drawings as various changes in the details of constructionmay be resorted to without departing from the spirit of the invention.For example, while the method, as described, embodies the step ofvibrating each unit stack 22 while simultaneously strapping the same, itis within the purview of the invention to vibrate the stack while undertransverse compression to produce the necessary interfacial abrasion andremoval of the products of abrasion and to thereafter resort to thestrapping operation while maintaining such transverse compression in theabsence of vibration. Such a procedure is not as effective as is thecase when vibration is maintained throughout the strapping operationsince without vibration the strapping is not assisted in its flow aroundthe four corners of the stack. However, strapping of a previouslyvibrated stack of bricks which are maintained under forced compressionwill produce a unit pack possessing greater stability than hasheretofore been possible with conventional brick packaging methods.Furthermore, while the various unit packs 12 are shown and describedherein as being circumscribed by fiat metal straps 14 under tension, thepresent method and apparatus contemplates the use of wire for thebanding operation. Therefore, only insofar as the invention hasparticularly been pointed out in the accompanying claims is the same tobe limited.

Having thus described the invention, what I claim and desire to secureby Letters Patent is:

1. The method of producing a substantially sand-free compact rectangularunit pack of kiln-produced bricks consisting of superimposed tiers ofindividual bricks disposed in face-to-face contiguous relationship andarranged in transverse rows, and a tensioned metal band encircling thepack and extending around the four longitudinal corners thereof andserving to hold adjacent bricks in contiguity, said method comprising:arranging the bricks to produce a stack in which the bricks assume apre-positioned relationship conforming to their final positions in thepack, placing the stack under transverse compression to force adjacentbricks hard against each other while simultaneously vibrating the stackbodily as a unit to produce interfacial abrasive rubbing of suchadjacent bricks against each other and consequent removal by gravity ofadhering kiln sand together with the products of abrasion, and finallytensioning the band about the thus treated stack to produce the unitpack.

2. The method of producing a substantially sand-free compact unit packof bricks as set forth in claim 1, wherein the step of tensioning theband about the stack is effected by drawing the band peripherally aboutsaid four longitudinal corners of the stack and is conductedsimultaneously with stack vibration and transverse stack compression tothe end that dynamic friction incident to the vibration will enhance theflow characteristics of the metal band in passing over said corners.

3. The method of producing successive compact rectangular unit packs ofkiln-produced bricks which are substantially free of kiln sand, eachunit pack consisting of superimposed tiers of individual bricks disposedin faceto-face contiguous relationship and arranged in transverse rows,and a tensioned metal band encircling the ack and extending around thefour longitudinal corners thereof and serving to hold adjacent bricks incontiguity, said method comprising: assembling the bricks of each packat a stacking station to produce a stack in which the bricks assume apre-positioned relationship conforming to their final positions in thepack, conducting the thus assembled stacks in longitudinal alignment ina forward direction to a pre-cornpression station, a strapping stationand an unloading station, successively and in the order named,subjecting successive stacks at the pro-compression station totransverse compression to force adjacent bricks hard against each otherWhile simultaneously vibrating the stacks bodily as a unit to produceinterfacial abrasive rubbing of such adjacent bricks against each otherand consequent removal by gravity of adhering kiln sand together withthe products of abrasion, and

maintaining such transverse compression and vibration of the succesivestacks at the strapping station while simultaneously tensioning thebands about the thus treated stacks to produce the unit packs.

4. Apparatus for packaging kiln-produced bricks and comprising: conveyormeans for transporting a plurality of closely positioned unit stacks ina longitudinal row forwardly in a longitudinal direction from a stackingstation, through a pie-compression station, and a strapping station toan unloading station successively and in the order named, means forindexing the conveyor to advance the stacks one unit stack at a time,said precompression station and said strapping station being disposed insuch close proximity to each other that a stack which is disposed at thestrapping station is in close proximity to the next adjacent followingstack at the pre-compression station, means at said precompressionstation and engageable with the opposite lateral sides of at least saidnext adjacent following stack for subjecting such stack to transversecompression to force the opposed surfaces of adjacent bricks againsteach other, means at said strapping station for likewise subjecting astack at said latter station to transverse compression, means at saidprecompression station for imparting high frequency vibration to saidnext adjacent following stack to produce interfacial abrasive rubbing ofsuch adjacent bricks against each other incident to transversecompression of such stack and consequent removal by gravity of adheringkiln sand together with the products of abrasion, and means at saidstrapping station for applying metal binder straps to a stack at saidlatter station.

5. Apparatus for packa ing kiln-produced bricks as set forth in claim 4,wherein the means at the pre-compression station for imparting highfrequency vibration to said next adjacent following stack comprises avibratory plate positioned in the path of movement of the stack andengageable with the underneath faces of such stack.

References Cited UNITED STATES PATENTS 2,917,991 12/1959 Segur 100-73,003,296 10/1961 Feldkamp et al. 53--198 XR 3,095,678 7/1963 Cliff etal. S3l98 XR 3,147,692 9/1964 Berncr 100-7 XR 3,238,864 3/1966 Patterson100-3 3,280,725 10/1966 Bartram 1007 XR BILLY J. WILHITE, PrimaryExaminer.

1. THE METHOD OF PRODUCING A SUBSTANTIALLY SAND-FREE COMPACT RECTANGULARUNIT PACK OF KILN-PRODUCED BRICKS CONSISTING OF SUPERIMPOSED TIERS OFINDIVIDUAL BRICKS DISPOSED IN FACE-TO-FACE CONTIGUOUS RELATIONSHIP ANDARRANGED IN TRANSVERSE ROWS, AND A TENSIONED METAL BAND ENCIRCLING THEPACK AND EXTENDING AROUND THE FOUR LONGITUDINAL CORNERS THEREOF ANDSERVING TO HOLD ADJACENT BRICKS IN CONTIGUITY, SAID METHOD COMPRISING:ARRANGING THE BRICKS TO PRODUCE A STACK IN WHICH THE BRICKS ASSUME APRE-POSITIONED RELATIONSHIP CONFORMING TO THEIR FINAL POSITIONS IN THEPACK, PLACING THE STACK UNDER TRANSVERSE COMPRESSION TO FORCE ADJACENTBRICKS HARD AGAINST EACH OTHER WHILE SIMULTANEOUSLY VIBRATING THE STACKBODILY AS A UNIT TO PRODUCE INTERFACIAL ABRASIVE RUBBING OF SUCHADJACENT BRICKS AGAINST EACH OTHER AND CONSEQUENT REMOVAL BY GRAVITY OFADHERING KILN SAND TOGETHER WITH THE PRODUCTS OF ABRASION, AND FINALLYTENSIONING THE BAND ABOUT THE THUS TREATED STACK TO PRODUCE THE UNITPACK.